Color stabilizers for detergents containing bacteriostats



' incorporation of bacteriostats in detergents for the pura tendencyon the part of certain of these bacteriostats arm? Patented Aug. 18, 1964 3,145,179 COLOR STABILIZERS FOR DETERGE CONTAINING BACTERIGSTATS Jane P. Mitoray audwillinm G. Bauer, St. Louis, Mo., 5

assignors to Monsanto Company, a corporation of Delaware No Drawing. Filed Non-24, 1958, Ser. No. 775,714

' 3 Claims. (Cl. 252-407) This invention 'relates tocompositions comprising a 1 detergent, a bacteriostat, and a stabilizing compound to minimize the tendency of the bacteriostat todiscolo'r the I detergent.

' Recent developments in the detergent industry, and 5 particularlywith respect to soaps, have resulted in the pose of inhibiting or destroying the growth of bacteria, fungi, and related organisms. However, there has been of a phenolic nature to discolor under alkaline conditions such as are present in detergents, especially when exposed to light. w

It is accordingly a primary purpose of this invention to provide compounds which will eliminate or minimize the tendency of these bacteriostats to discolor the soap.- A further object is to provide various formulations which will prove elfective in preventing or decreasing detergent discoloration under alkalineconditions when exposed to light. Further objects will be evident from the description that follows.

According to this invention it has been found after investigation of a large number of compounds that when small amounts of certain organic sulfur-nitrogen compounds are added to a mixture of a detergent and bacteriostat within the scope of the following formula OH OH where X is a member selected from the group consisting of sulphur and methylene, a is an integer from 1 to 4, and b is an integer from 1 to 4. Bacteriostats of the above structure include as repres'entatives thereof the 2,2'-thiobis(dichlorophenols), the

2,2 thiobis(chlorophenols), 2,2 thiobis(trichlorophenols), the bis(trichlorohydroxy) methanes, the bis(dichlorohydroxy) methanes, the bis(chlorohydroxy) methanes, and the like. In this connection see US. Patents 2,535,077 and 2,250,480. 1

In this connection by detergent is meant the well known organic non-ionic surface active compounds (see US.

1,970,578 and U.S.' 2,213,477 for examples) and the anionic surface active compounds which latter group includes the surface active'alkali metal sulfonates and sulfatesin addition to the preferred alkali metal fatty acid soaps (see US. 2,295,594) and mixtures thereof. ,In addition by the term-bacteriostat is meant any compound which is active either in inhibiting thegrowth of or destroying microorganisms such as bacteria and fungi although the term has particular reference to bacteria.

Specifically it has been found that detergent formulations containing, for example, 99.5 parts by weight of zinc dibutyl dithiocarbamate, z-inc diethyl dithiocarbamate,

zinc dimethyl dithiocarbamate, N,N'-dipheny1 thiourea (thiocarbanilide), Z-mercaptobenzothiazole, sodium d-ibutyl dithiocarbamate, sodium diethyl dithiocarbamate, and sodium dimethyl dithiocarbamate with the first five mentioned being the preferred group. In general any zinc, sodium, or potassium dialkyl dithiocarbamate will be found satisfactory. The above dialkyl group may have from 1 to 6 carbon atoms and compounds contemplated include zinc dihexyl dithiocarbamate, potassium dipropyl dithiocarbamate, sodium diamyl dithiocarbamate, potassium dimethyl dithiocarbamate, and the like.

The suitability of these compounds for minimizing discoloration is demonstrated by exposing soaps containing a bacteriostat and the color stabilizer compound to ultraviolet light. Representative of the results obtained from these experiments are the data set forth in the following tables. In each instance the number given in these tables represents percent reflectance with magnesium oxide taken as the standard at percent. It will be noted that there are two reflectance values given for each-soap-or soap formulation. These values represent an initial reading and a reading after 30 minutes of ultraviolet ray exposure. Each soap sample tested contained 99.5 parts byweight of soap and 0.5 part by weight -of-the bacteriostat selected from the group consisting of '2,2'-'thiobis(4,6-dihlorophenol); bis(3,5,6 trichloro 2 hydroxy-phenyl) methane; and 2,2'-thiobis (p-chlorophenol), The parts by weight of stabilizer employed usually varies from 0.01 to 0.5.

TABLE I Color Degradation of Bar Soap Containing 2,2'-Zhi0- bis (4,6-Dichlr0phen0l) (A), Pe

rcent Reflectance Color Degradation bis (4,6-Dichl0rophenol) (A),

(MgO: 100% Monochromatic filters Trl-stlmulus filters Color stabilizer Test ltem Green Blue Red Amber Green Blue None 808p 74-71 68-64 8683 80-77 78-76 61-58 0 Soap+0.5 A.-- 75-55 67-48 85-75 80-64 76-60 63-42 0.5 zinc dlbutyl d1- d0 75-61 64-55 84-80 77-70 75-65 59-45 thloearbamste. 0.25 zinc dlbutyl (11- .....d0 74-65 67-58 86-82 80-74 78-70 62-50 thlocarbarnate. 0.10 zinc dlbutyl d1- d0. 76-64 68-58 87-82 82-75 79-70 64-50 thiocarbemate. I 0.05z1n0 dlbutyl (11- .....d0 75-62 67-55 85-80 80-71 78-67 62-47 thioearbamate. v 0.025 21110 dlbutyl di- 76-65 69-58 87-81 82-74 80-70 6440 thloearbamate. I 0.01 zinc dibutyl 61- 77-65 69-57 87-80 82-73 80-70 66-50 thlomrbamate. 0.005 zinc dlbutyl (11- 77-64 70-57 87-80 83-71 81-68 -49 thiocarbamate. 0.11125 zinc dlbutyl 77-63 69-55 86-79 82-71 80-67 64-49 dlthlocarbamate. 0.25 zinc dlethyl dl- 73-64 66-54 83-80 80-70 77-68 61-47 thiocarbemate.

0.10 zinc dlethyl dl- 7 74-61 67-52 84-79 81-69 77-65 62-45 thl rbamate 0.25 zine dlmethyl 111- ....do 75-66 67-56 82-82 81-73 -70 62-49 thlocerbamate. 0.10 zinc dlmethyl dl- -...--d0 -66 66-55 85-82 81-73 78-70 62-49 thlooarbamate.

TABLE 11 Color Degradation of- Bar Soap Containing 2-,2'-Thiobis- (4 ,6-Dlchlorophenol) (A), Percent Reflectance 1 (MgO: 100% Monochromatic filters Tri-stimulus filters Color stabilizer Test item Green Blue Red Amber Green Blue 8081).--. 86-83 80-77 78-76 61-58 Soap+0.5 A--- 67-48 -75 76-60 -d0 69-56 86-81 82-71 1 80-68 63-47 68-54 85-79 81-69 79-66 62-46 70-58 86-82 83-73 81-70 64-51 70-59 86-82 82-74 81-70 65-51 69-54 81-70 81-70 80-66 63-47 0. 70-56 83-71 81-67 65-48 0.005 thlooarbanllld 70-51 84-77 81-67 80-63 63-43 0.0025 thlocarbanlllde. 69-57 84-77 81-67 79-63 63-45 TABLE III of Bar Soap Containing 2,2-Thio- Percent Reflectance Color stabilizer Test item Monochromatic filters Tri-stlmulus filters Green Blue Red Amber Green Blue 82-74 so-1o 64-45 TABLE IV (MgO =l00% Percent Reflectance Color Degradation of Bar Soap Containing 2,2'-Thiobis (4,6-Dichlorophenol) (A), Percent Reflectance Monochromatic filters 'Irl-stlmulus filters Color stabilizer Test item Green Blue Red Amber Green Blue None Soap 74-71 68-64 86-83 80-77 78-76 61-58 0. Soap-+0.5 B--- 74-63 67-56 85-80 81-70 78-07 61-48 0.1 thiocarbanllldedo 75-68 67-59 85-81 81-76 78-70 61-52 0.25 zinc dlbutyl- --do 73-67 66-60 83-82 79-75 76-74 02-53 dithiocarbamate. 0.1 zinc dibutyi- .----do 76-67 68-59 86-82 82-77 78-72 62-53 dithiocarbamate.

0.25 zinc dlethyl- ---.-do. 73-67 65-57 82-81 80-74 70-72 60-50 dithiocarbamate. 0.25 zine dlmethyl- ---do. 76-70 68-61 86-84 82-78 79-75 64-44 dithiocarbamate. 0.10 zinc dimethyl- -..--do 75-66 67-57 85-82 82-74 78-71 62-49 dithiocarbamate.

TABLE V Monochromatic filters 'lrl-stimulus filters Color stabilizer Test item Green Blue Red Amber Green Blue 68-64 86-83 80-77 78-76 61-58 61-41 78-70 75-59 68-51 54-36 rb lid 67-49 85-77 81-69 77-63 61-42 0.25 zinc dlbutyl- 63-52 81-78 77-69 74-67 59-45 dithiocarbamate. 0.1 zinc dibutyl- -d0 75-63 67-53 85-79 81-72 78-66 .60-45 dlthiocarbamate 0 25 zine dlethyl do 71-62 64-51 82-79 78-70 74-67 59-45 iocarbarnate 0 zinc diethyl- ----do 71-58 63-47 82-77 79-67 75-63 59-39 dlthloearbamate 0 zinc dimethyl do 73-63 62-52 82-77 80-72 76-69 61-44 dithioearbemate 0 10 zinc dimet do 73-61 65-49 83-80 80-71 76-67 61-41 dithiocarbamate.

From the above tables it will be apparent that although the presence of the bacteriostat markedly reduces the whiteness of the soap, the addition of the color stabilizer improves the whiteness of the soap in spite of prolonged exposure to ultraviolet light. In some instances it will be noted that the formulation of detergent, color stabilizer, and bacteriostat represents an improvement of whiteness over the soap and bacteriostat on the order of percent (see 0.1 2,2-thiobis(4,6-dichlorophenol) in Table V using blue monochromatic filter).

In general the parts by weight used of the color stabilizer varies from 0.01 to 0.5 part by weight for every 99.5 parts by weight of detergent and 0.5 part by weight of bacteriostat. While larger amounts of color stabilizer up to 10.0 parts by weight may be used, the upper limit will be determined by practical considerations.

The color stabilizer may be incorporated in the bacteriostatic detergent in the course of its manufacture. For example, in thecase of a soap, the color stabilizer may be added during the crutching, milling or similar operation. The color stabilizer may be dissolved in a suitable solvent prior to admixing with the soap. With frame soaps the color stabilizing compound may be added during the crutching operation. With milled soaps, the addition may take place during the milling operation. In general any method which results in the color stabilizer being uniformly incorporated into the detergent or soap is satisfactory. If desired, other components normally found in detergents or' soaps and mixture thereof may be added such as perfumes, water softeners, abrasives, and the like.

While this invention has been described with respect to certain embodiments, it is not so limited, and it is tc be understood that variations and modifications thereoi obvious to those skilled in the art may be made without departing from the spirit or scope of this invent-ion.

What is claimed is:

1. An antiseptic detergent composition consisting es sentially of an alkali metal fatty acid soap, -2,2'-thiobis (4,6-dichlorophenol), and from 0.01 to 10 percent lb weight, based upon the combined weight of the soap am the 2,2'-thiobis(4,6-dichlorophenol), of zinc dibutyl di thiocarbamate.

2. An antiseptic detergent composition consisting es sentiallyof an alkali metal fatty acid, soap, 2,2'-thiobis (4,6-dichlorophenol), and from 0.01 to 10 percent b1 weight, based upon the combined weight of the soap am the 2,2-thiobis(4,6-diehlorophenol), of Z-mercaptobenzo thiazole.

3. An antiseptic detergent composition consisting es sentially of an alkali metal fatty acid soap, bis-(3,5,6 triehloro-Q-hydroxy-phenyl) methane, and from 0.01 t 10 percent by weight, based upon the combined weight 0 the soap and the bis-(3,5,6-trichloro-Z-hydroxy-phenyl methane, of zinc dibutyl dithiocarbamate.

(References on following page) 7 I 8 References Cited in the file of this patent FOREIGN PATENTS 7 802,447 Great Britain Oct. 8, 1958 UNITED STATES PATENTS 472,269 Canada Mar. 20, 1951 2,154,341 Martin Apr. 11, 1939 9, 34 Australia Aug. 7, 1958 2,161,772 Cal-swell June 6, 1939 5 OTHER REFERENCES 2,184,040 Garner Dec. 19, 1939 2,680,122 Black et a! June 1, 1954 F1ore:v Soap and Samtary Chem1cals, December 1941, 2313,0711 Edelman et a] Nov. 12, 1957 30733 2,963,438 Harshman et aL 6, 1960 Shumard et al.: Soap and Samtary Chem1cals, Janu- ,971,917 Fusco et a1. Feb. 14,1961 10 1953,1134- 

1. AN ANTISEPTIC DETERGENT COMPOSITION CONSISTING ESSENTAILLY OF AN ALKALI METAL FATTY ACID SOAP, 2,2''-THIOBIS(4,6-DICHLOROPHENOL), AND FROM 0.01 TO 10 PERCENT BY WEIGHT, BASED UPON THE COMBINED WEIGHT OF THE SOAP AND THE 2,2''-THIOBIS(4,6-DICHLOROPHENOL), OF ZINC DIBUTYL DI-/ THIOCARBAMATE. 